Xp error winlogon.exe - badname

Looking for some help, when I try to boot up computer I keep getting error
winlogon.exe - badname
dllc.windows system32\kbdus.dll
Have tried to repair with os discs but not working, keeps going back to error.
Is there anything that I can do without reinstalling windows. I would like to be able to recover some files first?
Has this happened to other xp users?